A posting on an Islamic Web site by a group calling itself Ansar al-Jihad group claimed responsibility for kidnapping three Allawi relatives, and threatened to behead them in 48 hours if their demands aren't met.

They demanded that Allawi and his government release all female and male detainees in Iraq, and lift the siege on Fallujah.

"We promise Allah and his messenger that if the agent government doesn't respond to our demands within 48 hours, they (the hostages) will be beheaded."